This disclosure relates to protective coatings. Ceramic and metallic materials, such as superalloys, are attractive materials for use in articles that operate under severe environmental conditions. As an example, gas turbine engine components are subjected to high temperatures, corrosive and oxidative conditions, and elevated stress levels. In order to improve the thermal and oxidative stability of these components, various types of coatings have been used to protect the article from the elevated temperature conditions or corrosive/oxidative and stress-producing environments. Likewise, many other types of components or articles may also utilize protective coatings.